Optimizing exception handling in workflows using process restructuring

Abstract

Exception handling is the process by which a failure in a process is mitigated. Depending on the specifics of an exception, exception handers - specifications of exception handling processes - may range from halting a process, through attempts of activity reactivation, to an identification of an alternative path to successful completion of a process. Designing efficient exception handlers is not a simple task. By their very nature, exceptions are rare events that may result in poor design of exception handlers in terms of cost and logic. In this work we aim at improving exception handling performance in workflow management systems (WfMSs), a task which has been recognized as a fundamental component of WfMSs that is critical to their successful deployment in real-world scenarios. Our approach is based on the observation that when designing a business process as a workflow, a designer has some degree of freedom in streamlining actions. Therefore, we propose process model restructuring as a main tool in reducing the cost of exception handling. We believe that restructuring of a process model, based on exception efficiency consideration, can increase the overall productivity of the business process. Although the rarity of exceptions allows amortizing their costs over time we cannot ignore exception costs altogether. Therefore, we propose a cost-based approach to prioritize their impact on the workflow design. Our main contribution is the provision of a methodology for exception handling optimization at the workflow design phase. © Springer-Verlag Berlin Heidelberg 2006.